I started this class by writing on the board: "What do you have in common?" and explained what "in common" means. I asked, as a class, what they have in common and wrote their answers on the board ie. "We all are girls." "We all wear uniforms."
I then asked 2 students to come to the front, and with the help from the class, I wrote a few sentences about them. The sentence should change to: "They both have" .... "They both are...." and explained "both" as for just 2 people.
I underlined the verbs so they could see that the verbs changes and the pronoun changes.
In their notebooks, the students write #1-10 and a name of a student in the class next to it. (Try to get them to write the names in English, but this does take up more time). Then for each name they must think of something they have in common and write a sentence starting with "We both...." All 10 sentences should be different. I let my students get out of their desks and walk around a bit.
As they write their sentences, collect 8-10 incorrect sentences that you see. When they finish, write the incorrect sentences on the board to be copied and have them fix the mistakes. This is a great way to reinforce proof reading their writing and to improve their writing skills. Most can catch the mistakes, and if not, you correct it all together with 5 minutes left in the class. Also, it's annonymous, so the students won't know who's bad writing is on the board.
I tried this with my high level grade 1 and 2s (my classes have been streamed into Low and High) and it was quite successful!