1. Could you take a picture of me with the lake in the background?.

Key Points: take a picture of
Useful expressions when taking photos: 
(1). Will you please pose for your picture?
(2). How many exposures have you made?
(3). Get the waterfalls in the background, will you?
(4). You come out well in the picture.
(5). The photograph is really well taken.
(6). This photo flatters you.
(7). This photo has done you justice.

2. I wonder if you can drop by tomorrow evening.

Key Points: drop
(1). drop out
1). give up halfway
The marathon runner had to drop out with only three miles to go.
2). leave school
He dropped out because of the strict school rules.
(2). drop off
1). reduce
Business dropped off sharply during the recession.
2). become less
Interest in the book began to drop off.

3. They try to find ways to help solve the problems that contributes to crime in the first place.

Key Points: contribute/ in the first place
(1). contribute to ( be helpful to sth)
However, beyond just feeling good, happiness also contributes to our life, to our relationships.
(2). in the first place (emphasize the importance)
Why did you choose basketball in the first place?