Complete the sentences with prepositions. 1.it is a valentin serov. 2.mike is pencil. 3.i am biology. 4.we the puppet theatre at the weekend. 5.henry is his grandfather. ​

Derek: Hi, Sam. Haven't seen you for ages. How are you? 
Sam: Oh, Derek, is that you? It's been a long time since last summer. How are you?
Derek: I'm so happy to be back at camp. And how is your best friend Lucy? 
Sam: Oh, Lucy is great. She is in college now. She studies English Literature at Princeton University. 
Derek: Wow! That's really far away. How do you keep in touch? 
Sam: We do not meet very often, but she writes lots of e-mails and I phone her regularly. I don't like e-mails. 
Derek: So where is she spending her summer? You always come to camp together. 
Sam: Don't you  know her news?
Derek: No, what is it?
Sam: Lucy has found a summer job.
Derek: What does she do?
Sam: She is working with children.
Derek: Is she a teacher?
Sam: Not really. Actually, she's a counsellor in our camp. So I see quite a lot of her these days.
Derek: How wonderful! 
Sam: Isn't it? You can go and talk to her. She welcomes new campers in their cabins. Goodbye then.
Derek: OK. See you soon!

1. it is impossible to prevent, everything depends on the natural conditions.2. careful washing and heat treatment of vegetables and greens if they are watered with water from stagnant water bodies, do not drink raw water from stagnant water bodies.do not consume water from unverified sources. compliance with personal hygiene measures3. the first thing to do is to temporarily shelter the victims. organize the collection of funds and basic necessities. there are many examples when officials steal money allocated to victims or engaged in postsignals, put on the lists of injured people who have not suffered.therefore, the method is the best way to help create a separate independent fund that will collect funds and distribute aid, regardless of power structures.