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1. Boy's bullying has always attracted attention, because it is crudely obvious.

2. The percentage or letter-marking system is better than the pass/fail system, because marks motivate students to work harder.

Can I omit the comma before because in the above sentences?
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Comments  (Page 2) 
Yes; maybe:

1. Where's Teo?

— He's at home, because he's not feeling well.

2. Why is Teo still at home?

— He's at home because he's not feeling well.

MrP
1. He didn't go there because his sister was going to be there. (He did go there, but not because his sister was going to be there.)

2. He didn't go there, because his sister was going to be there. (He did not go there, and he decided not to because his sister was going to be there.)

An Introduction to English Grammar
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No
Hi Teo

I agree with the interpretations of your sentences.

(I have no idea what Anon disagrees with.)
Hi guys,

I've often pondered about the "because clause" as well.

Do you need a comma or not? And if so, when? I have found several things while reading other writers' pieces of work.

When they start a sentence like this: "S+V, because S+V" one of those V's (verbs) is the linking verb "be" (is, am, are, was, were ...). 19 out of 20 times, there will be a comma if one of the verbs is "the be verb."
For Example: A is B, because C does D.

- Phonics is the method of learning to read by assigning

The percentage or letter-marking system is better than the pass/fail system

A is B

, because

marks motivate students to work harder.

C does D

And, when there is a comma before the "because clause," it signifies that that it is possible to send that "because clause" to the front, making it a flip-flop sentence.

Because marks motive students to work harder, the percentage or letter-marking system is better that the pass/no pass system.

What do you think, Clive?
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