Можно ли про ручки (pens) сказать "они" (they)? jess - она или он?

Pen- исчисляемое, соответственно можно. jess- это и мужское и женское имя.

i am a big fan of social networking sites, especially vk and instagram  

it's really very interesting to browse other people’s vk pages, view their photos, and read the comments.

you can find some interesting people and send them your friend request.

also, you can save some wonderful photos and share them with your friends on vk.

it is also good for those people who have little to do and are always bored.

plus these sites allow you to share your life with your friends, both real and virtual.

the only problem with instagram and similar sites is that now i stay at home a lot and rarely go out.

in brief, it wonderful that i can live so active a life staying indoors!

1has helen ( written) the letter yet? 2 i (have lived) in a small cottage for 12 yaers. 3 she told me she (had worked) in england before. 4 i don't think she (will have bought) a computer by the end of the week. 5 when i arrived at the country house i realized that i (had lost) the keys.1 turn on the television, please. 2 her father works in a hospital. 3 she couldn't cope with last week. 4 on sundays the family always go to church. 5 tom was in prison 5 years ago. 6 she is at work. 7 would you like to go to the university with me?