We guarantee that we will replace the defective item with the new one
completely free of charge.
We:主詞 guarantee:及物動詞
that we will
replace the defective item with the new one completely free of charge
->整坨作為guarantee的受詞
結構為連接詞that + S + Vt + O...名詞子句 整坨當作guarantee的受詞
內部結構:
we will replace the defective item with the new one
completely free of charge
phr.replace A with B 以/用 B (來/去)取代/替換 A
the new one completely free of charge
the new one
->定冠詞the+屬性adj+不定代名詞one ...整坨為名詞 符合with + 名詞
one=item (以避免重複)
completely free of charge
->adv修飾free of charge
phr.free of charge adj.免費的
the new one completely free of charge
->定冠詞the+限定adj+指稱代名詞one+adv+述語adj

http://en.wiktionary.org/wiki/free_of_chargefree of charge是副詞例如: We guarantee that we will replace thedefective item free of charge. 也還是對的句子並不是勉為其難的"也"可以做副詞解 在此它就是副詞只是原po的句子讓它剛好也可以用形容詞來解釋想想其他句子: replace the defective item with itcompletely free of charge 或 replace the defectiveitem free of charge. 就會讓它無法以形容詞解釋或者replace it for you completely free of charge

免費換新品就是免費啊，哪來甚麼手續費商品費啊

誰說解釋成"副詞修飾動詞" 就會有你說的第二種意思?所以像"replace the defective item free of charge"這裡free of charge只能當副詞解 就會出現語意的含糊??又或者你認為這裡free of charge還是形容詞?照你這樣解釋 剛剛wiktionary的例子:They were giving the tickets away free of charge.由於free of charge是副詞 所以他們免費送出票的過程是不用錢的 但是票本身可能還是要再收錢??你說的就完全違背了free of charge的定義了阿Without any payment being required!

要判斷一個phrase是不是adverbial，一個不錯的方法是看這phrase能不能在句中移動，且仍保持整句原意:We guarantee that we will replace the defective item__free of charge__ with the new one. 這也是一個表達原意的說法。 前頭 B 的例子只是剛巧沒補上後頭的"withthe new one"(他的句子也確實可以有多種解釋，比如「免費換」(不會收任何費用)，但不是用全新品更換--只用"workingpart(s)"來更換(在美國)也是尋常）。不過呢，把"free ofcharge"當成adj(去形容那個"the new one")，以這角度來看整句反而會有這樣子的意思--> 是更換"免費的新品"喔，我可沒說不收你 labor charge, other fees ...但是這不是這個尋常說法的意思，所以以這角度來看沒有意義