David a lack of confindence and needs a lot of encouragement.

David a lack of confindence and needs a lot of encouragement. lack of和a lack of的区别? lack of 和 a lack of的区别 Lack anything,lack of lack作名词是be a lack of 还是be lack of 4.This item was not explained __ time.A. for lack B. lack C. for lack of D. lack of lack of lack of lack of a lack of prespecification什么意思 You lack a kind of courage. a lack of a lack of 与 no lack of 的区别那么补充一句：lack in 怎么用呢？ a lack of 和lack of 有什么区别?这俩个词组中lack都是名词,但是有什么区别呢? 【跪求】lack of 和 a lack of的用法,如题, lack of sth 和 a lack of 的区别最好用例句说明一下 lack相关短语的区别,be lack of,be lacking in ,lack sth,a lack of sth,等等并造句,如果还有其他相关短语,也请列出, lack的用法请问a lack of、be lacking in和lack for用法上有什么区别? lack是a lack of还是lack of 可数么?There is no lack of vegetable. a lack of money.缺乏金钱lack of packing缺少包装lack of penetration未焊透, 未熔穿lack of proportion比例失调怎么一会有a 一会没有?