Ответ:
1) is 2) has never worked 3) told 4) picked 5) began 6) was cutting 7) was singing 8) stuck 9) has arrived 10)cried 11) have just started 12) advised 13) was
14)said 15) looked 16) was standing 17) listened 18) was explaining 19) tried
20) have never tasted 21) did make