During the rainy season it takes longer for the clothes we hang in our rooms to dry.
When you hang the clothes inside during the rainy season, it takes a while for them to dry.
どちらの例文も「梅雨は部屋干しの洗濯物が乾きにくい。」というニュアンスです。
「梅雨の間」は、during the rainy season
It takes longer for the clothes we hang in our rooms to dry で「部屋に干した衣類が乾くのにもっと時間がかかる」
When you hang the clothes inside で「中に洗濯物を干す時」
It takes a while ... to dry で「乾かすのに時間がかかる」
ご参考になれば幸いです！
"The laundry doesn't dry easily when I hang it inside during the rainy season."
「部屋干しで洗濯物が乾きにくい」という表現を英語で行う場合、"The laundry doesn't dry easily when I hang it inside during the rainy season." や "It's hard to get the laundry to dry when it's hung up inside during the monsoon season." などとなります。
ここで "laundry" は「洗濯物」を、"dry easily" や "hard to get to dry" は「乾きにくい」を表しています。そして "when I hang it inside during the rainy season" は「梅雨シーズンに部屋で洗濯物を干す時」を指します。
日本 
アメリカ合衆国 
