•если короткий глагол заканчивается на гласную с согласной, тогда эта согласная удваивается: swim – swimming (плавать), stop – stopping (останавливаться), get – getting (получать так почему же с wait если добавить ing окончание, то получится waiting ?

Потому-что wait заканчивается на глухой

Удваивается в том случае, если этот глагол заканчивается на звонкий звук. а в случае со словом wait - наоборот. буква t - глухая, соответственно, удваиваться не будет)

Are you leving party now?  Present continiuos
Do you love him? Present simple
Have you ( or have you got )  brothers or sisters? Present Simple
Who cooks dinner tonight а здесь допустимо и Present Simple, и Present Continiuos, англ язык, к сожалению, богат на такие двойственности Who is cooking dinner tonight?
Does he send you an e-mail every day? Проверьте свой текст если send, то так, как я указала выше. Если sent, то Did he send you an e-mail every day? На 4 предложении настаиваю на варианте Who is cooking dinner tonight?

1 .Who's in charge of Elena. Today anyone not?-Yes. Three students not. 2.No one today is missing. All nine students here today. 3. Victor here?No he is missing. 4.What is the date today? -15 October. 5.Can I ask you a question? -Please. - Where's number 48?-I can't answer your question. Could you please ask Secretary. 6. As for English headphones ? 7.To turn on a tape recorder ? - Yes please. Turn off the tape recorder? - Yes please. Turn off the tape recorder? - No wait a bit . I start reading? -Yes. Erase from the Board ? - please. to open the window? there's no need. To read this sentence again? Yes please. 8 . please read louder. speak louder please. sing louder please. enough. 9. repeat the sentence 2 times . read the text 3 times. 10 .Let's go to the Dean during the break. Let's fix the mistakes in the dictation. 11 .Will not bring you a cool magazine? 12.You can do this exercise today? - Yes. you can write a text today? no . I can't write the text today. 13.These exercises are difficult. Repeat them. these lyrics lungs. you don't have to repeat them. 14.can sits .15. keep reading. 16.quieter please. the lesson is not over. How long to call?- only two minutes. 17.As proiznositsya the word palatalization. ? 18.how to spell the word pronunciation? 19.put the questions to the text. 20.please do not prompt. 21.bring your notebook please. 22. first, put the cassette and then turn on the tape recorder. now please rewind the tape. 24.You have classes on Friday? 3 hours ago