2.Form negative sentences: 1) He played handball. - He ________ handball. 2) Susan waited in the kitchen. - Susan _ in the kitchen. 3) I made the beds. - I ____ the beds. 4) They cleaned the classroom. - They the classroom. 5) She asked a lot of questions. - She a lot of questions. 6) The friends got new computers. - The friends _ new computers. 7) I was in Sofia last weekend. - I __ in Sofia last weekend. 8) You built a house. - You a house. 9) Christian bought a new guitar. - Christian _ a new guitar. 10) We went shopping. - We ______________ shopping.

Explanation: The verb tense is Simple Past and the verb is regular (to play), which means that the sentence needs the auxiliary did+not (didn't in contracted form) and the verb must be back to its infinitive form by removing the suffix "ed".

2) Susan didn't wait in the kitchen.

Explanation: The verb tense is Simple Past and the verb is regular (to wait), which means that the sentence needs the auxiliary did+not (didn't in contracted form) and the verb must be back to its infinitive form by removing the suffix "ed".

3) I didn't make the beds.

Explanation: The verb tense is Simple Past and the verb is irregular (to make), which means that the sentence needs the auxiliary did+not (didn't in contracted form) and the verb must be back to its infinitive form.

4) They didn't clean the classroom.

Explanation: The verb tense is Simple Past and the verb is regular (to clean), which means that the sentence needs the auxiliary did+not (didn't in contracted form) and the verb must be back to its infinitive form by removing the suffix "ed".

5) She didn't ask a lot of questions.

Explanation: The verb tense is Simple Past and the verb is regular (to ask), which means that the sentence needs the auxiliary did+not (didn't in contracted form) and the verb must be back to its infinitive form by removing the suffix "ed".

6) The friends didn't get new computers.

Explanation: The verb tense is Simple Past and the verb is irregular (to get), which means that the sentence needs the auxiliary did+not (didn't in contracted form) and the verb must be back to its infinitive form.

7) I wasn't in Sofia last weekend.

Explanation: The verb tense is Simple Past and the verb is "to be", which means that the sentence needs verb "to be" to be followed by "not", since verb "to be" is one of those verbs that can also be used as an auxiliary verb.

8) You didn't build a house.

Explanation: The verb tense is Simple Past and the verb is irregular (to build), which means that the sentence needs the auxiliary did+not (didn't in contracted form) and the verb must be back to its infinitive form.

9) Christian didn't buy a new guitar.

Explanation: The verb tense is Simple Past and the verb is irregular (to buy), which means that the sentence needs the auxiliary did+not (didn't in contracted form) and the verb must be back to its infinitive form.

10) We didn't go shopping.

Explanation: The verb tense is Simple Past and the verb is irregular (to go), which means that the sentence needs the auxiliary did+not (didn't in contracted form) and the verb must be back to its infinitive form.