Jawaban:

1. I am havinglunch when shecomes.
2. They are studyingwhile their parentis having a meeting.
3. Denia dropsthe glass while sheis drinking the tea.
4. Aska is sleepingwhen Rinaenters.
5. Ardian washesthe car while his motheris preparing the food.
6. Mr. Lubis callsPrita while sheis studying.
7. When Lia looked for the book, Andi was reading it.
8. Mrs. Neny is teachingwhen our headmasterenters our class.
9. Audrey findsthe wallet while sheis cleaning the floor.
10. Ruth is playingthe piano when his fathercalls her.

Penjelasan:

Present Continuous Tense is the tense that we use to express actions that are happening at the moment. The general formula is subject + to be (am, is, are) + Verb-ing + object.

If we want to make compound sentences with Present Continuous Tense sentence, we can make the other sentence also in the Present Continuous Tense form or in the Present Simple Tense (subject + V1), depends on the option that we have for the sentence (whether the to be exists (Present Continuous) or not (Present Simple)).

The word is and was will also determine whether the sentences are present tense or past tense sentences (for example, question number 7 is a past tense sentence because the word was).

Simple Past Tense: Subject + V2

Past Continuous Tense: Subject + was/were + V-ing

Demikian penjelasan saya, semoga dapat dimengerti. Mohon maaf bila ada salah kata. Jika anda puas dengan jawaban saya, bisa dijadikan jawaban tercerdas. Terimakasih :)