be in leaf
US /biː ɪn liːf/
UK /biː ɪn liːf/

慣用句
1.
葉が茂る, 葉が出ている
to have leaves, especially after a period of not having them (like in winter)
例:
•
The trees will soon be in leaf again.
木々はすぐにまた葉が茂るだろう。
•
By spring, all the bushes should be in leaf.
春までには、すべての低木が葉が茂るはずだ。
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