Radical 103 疋 stands for clothing or bales of cloth. In the Hanzi-Trainer, it is used synonymously with the correct 正, because it seems helpful for the explanations and the interpretation clothing/cloth bale would be in conflict with other radicals.
Vocabulary
延长
yán cháng
to prolong, to extend, to delay
1062
延长
yán cháng
1962
延迟
yán chí
to delay; to postpone; to keep putting sth off; to procrastinate
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