$11.$ $B$

- Dòng thứ bảy của đoạn văn 1: "I’ve learnt by giving mum and dad a hand". 

$12.$ $C$

- Dòng thứ  ba của đoạn văn 2: "Unfortunately, no one has wanted tables like that for years".

$13.$ $B$

- Dòng thứ tư của đoạn văn 3: "I’d also started an internet business, which was doing so well it was taking up every spare minute I had". 

$14.$ $A$

- Dòng thứ hai của đoạn văn 4: " I couldn’t believe it when she told me there’d be a thousand visitors, she comments".

$15.$ $A$

- "I’m a young furniture designer, whose work has appeared in several design shows and is sold in many city furniture shops".