Ответ:

А.

1. it's a fact that,

studies show that,

2. research has show that,

the research indicates that

3. i'm certain that

it's possible that

4. it's certain that

i know that

B.

1. a. mobile phones make life easier.

b. mobile phones can have disadvantages.

2. a. studying abroad is paid and requires a considerable amount of money.

b. studying abroad improves other language courses as well .

3. a. sleep helps improve blood circulation

b. person can see the future while sleeping

Объяснение:

еще один Сасори)