с дз Variant - 1
Put the verb in the first sentence in the Past.
1 They write that their work is very fruitful.
2 I think the Competitions will be difficult tomorrow
3 We are surprised that they can't understand it.
4 He says he didn't know the answer to this question.​

The Unfortunate Tandem

It happened while Mr Harris and his wife sitting on the tandem behind him (0) __were cycling__ (to cycle) through Holland. As the roads (1) _were stony, Harris asked his wife to sit tight. She (3) _could not explain later why she (4) _thought her husband (5) had ordered her to jump down. And she did so. Harris (6) went go on without turning his head. He (7) believed his wife (8) was sitting behind him.

Mrs Harris (9) found herself on the road alone.

At first, she (10) supposed her husband (11)wanted simply to show his skill and he (12) would return) soon when he (13) reached the hill. But her husband (14) disappeared in the wood.

She (15) began to cry as she (16) had no money, and she (17) did not know Dutch.

People (18) thought she (19) had lost something so they (20) took her to the police station.

Meanwhile, Harris (21) was cycling with great pleasure. But soon he (22) felt wrong. He (23) looked back but (24) saw nobody there.

While thinking how to find his wife he (25) met some local people. They (26) were sure he (27) would find his wife at the police station. There he (28) was asked when, where and why he (29) had lost his wife.

The meeting of Mr Harris and his wife (30) was not a tender one.

Be careful on the roads!

1. Now the whole world will have to believe that mankind is destined to inhabit, if not all, many planets in the solar system.2. If someone had said this fifty years ago, he would have answered that about it and think it is impossible. 3. The skeptics who said that this cannot be, we must acknowledge that we are destined to be witnesses of the interplanetary flights. 4. In order to launch the rocket into interplanetary space, scientists had to make precise calculations to know where to aim the rocket. They decided that it must go in the vicinity of the moon. 5. I believe that the Moon may be, will serve as a base for interplanetary flights. 6. Scientists think that the moon must be no atmosphere. 7. The difficulties we have to overcome in order to create a passenger interplanetary missiles, very high. But we will surely overcome them.