Study the examples. When do we use any-
and some-?
Is anyone from school going?
Someone you like will be there.
There isn't anywhere to play tennis.​

1. She (has/had been sitting) at the window since 10 o'clock. (оба варианта применимы, т. к. нет привязки ко времени)
2. He will (be training) from 6 till 8 o'clock next Friday.
3. I didn't speak to him because he (was making) expirement.
4. Now they are ( deciding) where to go for the Holyday this summer.
5. By 5 o'clock the device (had been operating) for 3 hours and didn't stop.
6. I'd like to know what (has) happened to him. (оба варианта применимы) 7. By this time tomorrow the train will (have left) 

doubts appear / arise — сомнения появляются, возникают

to appear on the horizon — появляться на горизонте

recognizance to appear when called on — обязательство явиться в суд по вызову

to appear far away — показываться, появляться вдали

to appear ill — выглядеть больным

to appear in equation — входить в уравнение

to summon to appear — вручить приказ о явке в суд

to appear in the case — выступать по делу

to appear on the cheap side — разг. прибедняться

appear before the court — представать перед судом