We are responsible to replace the defective ones. 

我們保換質量不合格的產品。 

It's really something wrong with the quality of this consignment of bicycles. 

這批自行車的質量確實有問題。 

I regret this quality problem. 

對質量問題我深表遺憾。 

We hope that you'll pay more attention to the quality of your goods in the future. 

希望貴方將來多注意產品的質量問題。 

The workings of these machines are inaccurate. 

這批機器運行不準。 

Upon arrival, we found the shipment of wool was of poor quality. 

貨到后，我們發現羊毛的質量較差。 

The quality of the fertilizer is inferior to that stipulated in the contract. 

化肥質量次于合同中規定的。 

The quality of this article cannot qualify for first-class. 

這批商品的質量不夠一等品。 

If you find the quality of our products unsatisfactory, we're prepared to accept return of the rejected material within a week. 

如果貴方對產品質量不滿意，我們將在一星期內接受退貨。 

More than 300 watches are not up to standard. 

有300多塊手表不合質量標準。 

Words and Phrases 

bad quality 劣質 

low quality 低質量 

inferior quality 次質量 

to be responsible for 對...負責 

inaccurate 不精確的 

poor quality 質量較差 

to be inferior to 次于... 

first-class 一等品 

unsatisfactory 不滿意的