TOEIC Grammar Trap · Part 5

TOEIC Trap: Because vs Because Of vs Due To

Because, because of, and due to all point to a reason. TOEIC tests whether the reason is a full sentence or a reason thing.

This page extends the basic Because vs Because Of decision. If you also confuse reason and contrast, read Because vs Although.

The event was cancelled because the weather was dangerous.

The event was cancelled because of dangerous weather.

The event was cancelled due to dangerous weather.

Core TOEIC rule: because + reason sentence. because of / due to + reason thing.

The 7-second choice

Do not start with translation. Look after the blank.

Reason sentencethe manager was absent
Reason thingthe manager’s absence
Formal reason thingdue to the delay

Because: use it before a reason sentence

Because is followed by a small sentence. You can usually see a person, thing, or situation doing something.

The meeting was postponed because the director was unavailable.

The order was delayed because the supplier sent the wrong parts.

The client approved the proposal because the estimate was reasonable.

Because of: use it before a reason thing

Because of is followed by a thing, event, situation, or short reason phrase.

The meeting was postponed because of the director’s absence.

The order was delayed because of a supplier error.

The client approved the proposal because of the reasonable estimate.

Due to: more formal reason thing

Due to often sounds more formal than because of. In TOEIC, it usually appears before a reason thing.

The office will be closed due to building maintenance.

The delivery was delayed due to severe weather.

The event was cancelled due to low registration numbers.

Fast check: if the words after the blank are not a full sentence, because of or due to may be correct.

The TOEIC trap

TOEIC often gives you a reason, but the answer depends on the form after the blank.

Correct: The shipment was delayed because heavy rain flooded the road.

Correct: The shipment was delayed because of heavy rain.

Correct: The shipment was delayed due to heavy rain.

Trap: The shipment was delayed due to heavy rain flooded the road.

Common TOEIC business signals

becausethe system crashed
because ofthe system failure
due totechnical problems
becausesales increased
because ofincreased sales
due tostaff shortages

Small words around the blank matter

TOEIC often gives the answer through small words such as the, a, possessive forms, or a full sentence after the blank.

The launch was postponed ___ the software had not been tested.

Signal: the software had not been tested = reason sentence.

Answer direction: because.

The launch was postponed ___ software problems.

Signal: software problems = reason thing.

Answer direction: because of / due to.

Quick TOEIC check

1. The meeting was cancelled ___ the manager was ill.

2. The meeting was cancelled ___ the manager’s illness.

3. Production stopped ___ a shortage of materials.

4. The invoice was rejected ___ the address was incorrect.

Fast-reader mistake

Fast readers often recognise the reason and stop checking. But TOEIC is not only asking, “Is this a reason?” It is asking, “What form is the reason?”

Bad shortcut: “It means reason, so any reason word is fine.”

Better shortcut: “After the blank, do I see a reason sentence or a reason thing?”

One-second tool

Use this shortcut:

because + full reason sentence.

because of + reason thing.

due to + reason thing, often more formal.

Final takeaway

TOEIC reason-connector questions are structure questions. The meaning is similar, but the shape after the blank decides the answer.

Look after the blank, name the reason type, and move on.

What’s the difference between “because” and “because of”? “Because” is followed by a full sentence. “Because of” is followed by a noun. Example: I stayed home because it was raining. I stayed home because of the rain. When do I use “because”? Use “because” when what follows has a subject and a verb. Example: She was late because the train stopped. Can I say “because of he was late”? No. That’s incorrect. Use “because” before “he was late.” Say: He was late because he missed the bus. What comes after “because of”? A noun or noun phrase comes after “because of.” Example: The delay was because of traffic. Is “due to” the same as “because of”? Almost, but not always. “Due to” must come after a form of “be,” like “is” or “was.” Example: The delay was due to traffic. Can I start a sentence with “because of”? Yes. Example: Because of the storm, the event was cancelled. Is it wrong to say “due to he was late”? Yes. That is incorrect. Use “because” instead. Say: He was late because he missed the train. When do I use “due to”? Use “due to” after a form of “be” (like is, are, was, were) and before a noun. Example: The cancellation was due to rain. Which is more formal: “because of” or “due to”? “Due to” is a little more formal, but both are used often. Use whichever fits the sentence pattern. Can I use “because” in the middle of a sentence? Yes. Example: He stayed home because he felt sick. Can I say “the flight was cancelled because of it was snowing”? No. That is incorrect. Say: The flight was cancelled because it was snowing. Or: The flight was cancelled because of the snow. What is the most natural way to explain a reason? Use “because” if you have a full sentence after. Use “because of” if only a noun comes after. Do “due to” and “because of” mean the same thing? Yes, they have the same meaning, but they follow different sentence patterns. Can I use “due to” at the start of a sentence? Only if the sentence starts with “It was due to…” or something similar. Example: It was due to a mistake. What’s wrong with “because of she was sick”? It has a sentence after “because of,” so it’s incorrect. Say: She stayed home because she was sick. Is “due” the same as “due to”? No. “Due” by itself doesn’t work in this kind of sentence. Say: The problem was due to poor planning. Can I say “He left due to tired”? That sounds unnatural. Better: He left due to tiredness. Or: He left because he was tired. What do I look for after the blank on TOEIC questions? If it’s a noun, use “because of” or “due to.” If it’s a sentence, use “because.” Can I say “She cried because of she failed”? No. That’s wrong. Say: She cried because she failed. Or: She cried because of her failure. Why does TOEIC ask about these phrases so often? Because they sound similar but follow different patterns. It checks if you notice what comes next — a noun or a full sentence.