I don't like it when my friends arrive at my house unannounced.
I don't like it when my friends show up at my place without letting me know first.
ーI don't like it when my friends arrive at my house unannounced.
「友達が連絡もなく家に来るのは好きじゃない」
unannounced で「来訪を告げずに・予告なしに」
ーI don't like it when my friends show up at my place without letting me know first.
「友達が先に私に知らせず家に来るのは好きじゃない」=「友達が連絡もせず家に来るのは好きじゃない」
to show up at で「〜に現れる・姿を見せる」
without letting me know で「私に知らせることなく」
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