It's hard to make a profit buying and selling stocks.
It's hard to make money on the stock market.
ーIt's hard to make a profit buying and selling stocks.
「株の売り買いで利益をあげるのは難しい」
it's hard to ... で「…するのは難しい」
to make a profit で「利益をあげる・儲ける」
to buy and sell stocks で「株の売買をする」
ーIt's hard to make money on the stock market.
「株取引でもうけるのは難しい」
to make money で「儲ける・稼ぐ」
on the stock market で「株取引で」
ご参考まで！
カナダ 
