Is it correct to say i heard the problem discussing or discussed​

they will have planted trees in their garden by 7 o'clock tomorrow в future in the past будетиметьтакойвид: they would have planted trees in their garden by 7 o'clock tomorrow. соответственно вопросы будут следующие:

would  they have planted trees in their garden by 7 o'clock tomorrow?

would  they have planted trees or flowers in their garden by 7 o'clock tomorrow?

who would  have planted trees in their garden by 7 o'clock tomorrow?

what would  they have planted in their garden by 7 o'clock tomorrow?

where would  they have planted trees by 7 o'clock tomorrow?

when would  they have planted trees in their garden?

what would  they have done in their garden by 7 o'clock tomorrow?

they would have planted trees in their garden by 7 o'clock tomorrow, wouldn’t they?  

the tiger is the largest cat species, reaching a total body length of up to 3.3 metres and weighing up to 306 kg. their most recognizable feature is a pattern of dark vertical stripes on reddish-orange fur with lighter underparts. they have exceptionally stout teeth, and their canines are the longest among living felids, with a crown height of up to 74.5 mm.they are territorial and generally solitary but social animals, often requiring large contiguous areas of habitat that support their prey requirements. this, coupled with the fact that they are indigenous to some of the more densely populated places on earth, has caused significant conflicts with humans. in zoos, tigers have live for 20 to 26 years, which also seems to be their longevity in the wild.

1) can   я не могу прийти к тебе, потому что я слишком занят.

2) should/must   тебе следует/ты должен прочитать это два или три раза, потому что он сложный.

3) may     могу я войти?  

4) can   он может сделать это, если захочет.

5) can     ты умеешь что-нибудь готовить?

6) could/must/had to   ты мог/должен был навестить виктора вчера, но ты не сделал этого.

7)   be able to   он сможет играть лучше, если будет много практиковаться.

8) be able to     ты сможешь принять участие в игре,   если тебе разрешит тренер

  удачи : ) 

there are 15 tables in our class   our teacher is kind     she works very hard     board in our class is big     it is blue and nice