VI.

1. Yes, it is

2. The symptoms of a headache are various: People see black dots and bright spots in front of their eyes or have pains only on one side of the head,..

3. People have headache when they work too hard or they are too nervous about something.

4. They can prevent headache by changing their diets or their lifestyles or simply by going to bed.

V. 

- The woman whom you saw yesterday is my teacher of English.

or My teacher of English is the woman whom you saw yesterday.

- We don't have enough money so we can't buy that house.

III.

1. If I had money, I could/ would buy a car.

2. We do the test very well although it's difficult.

                                       CHÚC ANH/ CHỊ HỌC TỐT!

@sakura

Trang 1:
1. Yes, it is
2. People can see black dots or bright spots in front of their eyes. They also have pains on one side of the head. Sometimes when the pain goes away, the head is sore.
3. People have headache when they work too hard or they are too nervous about something.
4. People can prevent headache by changing their diets and their lifestyles or simply by going to bed.

Trang 2:
1. The woman whom you saw yesterday is my teacher of English.
2. We don't have enough money, so we can't buy that house.

Trang 3
1. If I had money, I would buy a car
2. We did the test well although it was difficult