I urgently need help with a couple of sentences. Can you also check my previous post. I need to prepare the letter for tomorrow. Thank you.

1) The lady at the bottom left of the photo (is "in" the bottom a mistake when describing a photo?)
2) How long is it since you knew Peter?
(Wrong: I believe the only possible sentence is: How long have you known Peter?)
3) She is wearing a jacket with a long silk dress under it (underneath is a mistake?)

1) Both "at" and "in" are fine.

2) You're right.

3) No. Underneath is not a mistake. However, you can end the sentence after dress.

Sure! I'd be happy to help you with your sentences.

1) When describing a photo, it is more common to say "at the bottom left of the photo" rather than "in the bottom left of the photo." So your initial sentence is correct!

2) You're right, the sentence "How long is it since you knew Peter?" is not the most common way to ask that question. The more natural and commonly used sentence is "How long have you known Peter?" This construction with the present perfect tense is a way to inquire about the duration of a past action that started in the past and continues until now.

3) Both "under it" and "underneath" can be used to describe the position of the long silk dress in relation to the jacket. So, both "She is wearing a jacket with a long silk dress under it" and "She is wearing a jacket with a long silk dress underneath" are correct. It's just a matter of personal preference which one you choose to use.

As for checking your previous post, as an AI, I don't have the ability to access or review previous conversations or posts. However, if you'd like me to review a specific sentence or provide guidance on writing a letter, feel free to ask, and I'll be happy to assist you!