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to lean against; to lean on; to recline on
to lie heavy (on the stomach); to be uneasily digested
ソファにもたれてテレビを見ていた。
I was watching TV while leaning on the sofa.
食べ過ぎて胃がもたれているので薬を飲んだ。
I ate too much and my stomach feels heavy.
少年は大きな木の幹にもたれた。
The boy leaned against the trunk of a large tree.