Besides… Also and One Time / Once

除(chú) 了(le) ..还(hái) ... Besides… also

The usage of除(chú) 了(le) ..还(hái) ... Besides… also
除(chú) 了(le) ..还(hái) ... is often used as a pair to connect two items with the meaning of “in addition to A, there is B”. 以(yǐ) 外(wài) is optimal depending on the length of the structure. If a negative statement follows除(chú) 了(le) ...以(yǐ) 外(wài), the structure corresponds to “except A, no others”.

Examples:
1, Besides Chinese, he can also speak Japanese.
他(tā) 除(chú) 了(le) 会(huì) 说(shuō) 汉(hàn) 语(yǔ) 还(hái) 会(huì) 说(shuō) 日(rì) 语(yǔ) 。

2, Besides a debit card, I also want to apply for a credit card.
除(chú) 了(le) 提(tí) 款(kuǎn) 卡(kǎ) 以(yǐ) 外(wài) ，我(wǒ) 还(hái) 想(xiǎng) 申(shēn) 请(qǐng) 一(yí) 个(gè) 信(xìn) 用(yòng) 卡(kǎ) 。

3, Except for US dollars, I have no other currency.
除(chú) 了(le) 美(měi) 元(yuán) 我(wǒ) 没(méi) 有(yǒu) 别(bié) 的(de) 钱(qián) 。

One time / once 一(yī) 下(xià)

The usage of一(yī) 下(xià)
An action verb attached by一(yī) 下(xià) may denote” just do something (for a little while) ”. It can make the tone of voice moderate and more polite.

Sentence pattern: Subj. + V + 一下 + Obj.

Examples:
1, This is the check-in form, please fill it out.
这(zhè) 是(shì) 住(zhù) 房(fáng) 登(dēng) 记(jì) 表(biǎo) ，请(qǐng) 您(nín) 填(tián) 一(yī) 下(xià) 。

2, Take a look. Is this a picture of you?
你(nǐ) 看(kàn) 一(yī) 下(xià) ，这(zhè) 是(shì) 你(nǐ) 的(de) 照(zhào) 片(piān) 吗(ma) ？