Consegue encontrar o erro? (B2, C1)

What’s up, folks? Preparei um exercício para alunos avançados, atendendo em especial às necessidades de estudantes brasileiros. Todas as sentenças ulteriores possuem um erro, em geral cometidos por alunos cuja língua materna é o Português. Num post futuro, colocarei as respostas para vocês. Grande abraço, pessoal!

1) Find the mistake.

a) I know Carl since my childhood.

b) Actually people buy more houses than in the past.

c) Her experience meant she had a good advantage over her opponent.

d) I’ve started a new job a few weeks ago.

e) Less women live at their husbands’ expenses nowadays.

f) Jason is at the hospital. He has had an accident.

g) The relationship among these three sections of the economy.

h) Cost of life is quite expensive in London.

i) None of my parents wanted me to marry him.

j) I have studied really hardly for the test.