Ответ:
a) Jack broke his leg yesterday.
b) ☑
c) ☑
d) ☑
e) ☑
f) She is my best friend and I have known her for fifteen years.
g) ☑
h) Mel has lived in Malaga since 1998.
i) He's been to London twice.
j) ☑
k) He wrote (если он уже умер) / has written (если еще жив) ten bestselling novels.
l) ☑
m) When have you gone to Rome?