at which infants smile when spoken to,say "a-goo",bebble and coo 是the age的定語(yǔ)從句.
全句翻譯：他們說嬰兒在有人跟他們說話時(shí)會(huì)微笑、會(huì)說“啊咕”、波波和咕咕的年齡預(yù)示著將來的發(fā)展,并且可能是指向?qū)W習(xí)的重要線索.
語(yǔ)法成分分
{主語(yǔ)They} {謂語(yǔ)say} {賓語(yǔ)從句that [主語(yǔ)the age] [定語(yǔ)從句at which (主語(yǔ)infants) (謂語(yǔ)smile) (狀語(yǔ)從句when spoken to) ,(謂語(yǔ)say) (賓語(yǔ)"a-goo",bebble and coo)] [謂語(yǔ)foreshadow] [賓語(yǔ)later development] and [謂語(yǔ)may be] [賓語(yǔ)important clues] [定語(yǔ)pointing to learing]}.
希望大中小括號(hào)的層次{ [ ( ) ] }還算清晰
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