Sajdah and Jalsah

Q: Should an imam read the extra duas in jalsa and qaumah when performing salaah in jamaat? Or are these not to be read while performing jamaat?

Q: Is it permissible to make dua in Sujood during the salaah? Also, does this dua have to be in Arabic or can it be in any language? I have heard that if dua is made in any other language other than Arabic in sujood during the salaah, then the Salaah is not valid. Is this correct?

Q: Is it acceptable if I recite subhaana rabbial azeem in Ruku and subhaana rabbial a'la in sujud one time only instead of three times in the case when there is limited time available. For example I am performing Sunnah Salaah and Jamat has started or Qadha time is near etc.

Q: What extra Duas can be made in Jalsa, sujood and qiyaam?

Q: Can a person read the following Dua in his Fard Salaah:  حمدا كثيرا طيبا مباركا فيه after reading: ربنا و لك الحمد, in ruku', similarly can he read in jalsah: اللهم اغفرلي و ارحمني و عافني و اجبرني و ارزقني and if he is a muqtadi can he read these two dua's?

Q: Is it sunnat to join your own ankles in ruku and sajdah?

Q: When I make sajdah, I am not satisfied and I push my head too hard. I want to know the correct way of making sajda. How much pressure is requried? Where exactly should the floor touch the nose and forehead? Anywhere or some precise position is required?

Q: When performing Salaah behind the Imaam, in the sujud after saying a few times "subhana rabbiyal alaa" somehow I was about to say "sami Allahu liman hamidah" but as soon as i said "sami Al" I realisized and cutt off and continued saying "subhana rabbiyal alaa". Now was my prayed invalidated since I cutt of at the half? Must I repeat it?

Q: My question is that when we pray Fardh salah behind the Imam should we recite anything in between the 2 sajdahs or it is sufficient that Imam recite?

Q: For males and females- where should the thumbs be kept in sajdah- in line with the ears or eyes?