Well, never mind. That's just my level of English.
It can't be helped. My English is still at this level.
Never mind. I did my best.
「しょうがない、私の英語力はこんなもんだ」＝ Well, never mind. That's just my level of English. / It can't be helped. My English is still at this level. / Never mind. I did my best.
ボキャブラリー
しょうがない、し方がない ＝ never mind / it can't be helped
level of English ＝ 英語のレベル
do one's best ＝ 頑張る
I guess it can't be helped. That's just how my English is.
I guess there's not much I can do about my English. That's just the way it is.
この場合、次のような言い方ができますよ。
ーI guess it can't be helped. That's just how my English is.
「仕方がないか。それが私の英語だよ」
ーI guess there's not much I can do about my English. That's just the way it is.
「私の英語についてできることは限られている。そんなもんさ」
ご参考まで！
イギリス 
カナダ 
