1. mother.

2. father

3. father or mother

4. father and mother

1. Present contunuous tense

2. Past perfect tense

3. Past contunuous tense

4. Past indefinite tence

1. natural

2. rational

3. unsocial

4. wild

1. One type of heart disease

2. heart attack

3. heart failure

4. be disheartened

1. A

2. An

3. The

4. This