Кто такой Сигма (sigma)?

Тест

1) Rob........ his dog now. (walk)

2) she......... her exam next month. (take)

3) I............... the guitar. (never play)

4) Jane.........her friends every evening. (call)

5) We.............. this cafe. (already, visit)

6) Mark..............his book since last year. (write)

7) They.........me for their wedding yesterday. (Invite)

8) I.............. my clothes now. (Wash)

9) My parents....... from Monday to Friday. (Work)

10) Harry's sister.......... her exam recently. (Pass)

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