改错：1.Grandma and I go to a big shopping mall.2.We play a lot of computer game.

1.Grandma and I go to a big shopping mall.
1）这里用go很牵强，但是如果一定要用也不算错；最好是用went
2）mall本来就有big的意思，再加big有点重复；如果实在要说明这个mall很大可以用huge或colossal
参考：Grandma and I went to a huge shopping mall.

2.We play a lot of computer game.
1）play的时态也不太好；可以用完成时have played
2）game是一个[c.n.]；/pl/form是games
参考：We have played a lot of computer games.

按表达习惯
I WENT TO A BIG SHOPPING MALL WITH MY GRANDMA
WE HAVE PLAYED A LOT OF COMPUTER GAMES

1.go 应该为went
2.play 应该为played
game应该为 games

go-went 或 go-are going
play-played

还有 a lot of 应该改为lots of 会更好

went
games