Please proofread the following sentences
1. Your teacher asked you to pair up with another classmate to give a speech in an assembly. The speech should include the mission of UNICEF and its work.
2. What is the lifespan of a dog?
So how to change that?
But there is no change here.
tospeak to somebody
speak to a group of people
speak to an assembly
speak to the people assembled there
give a speech to the people
give a speech to the people at assembly