Learn French: Chaque expatrié a le mal du pays de temps en temps. - Each expatriate is homesick from time to time.

In French, being homesick is expressed with the verb avoir (to have). The exact expression is avoir le mal du pays, so instead of saying someone 'is' homesick, French speakers say they 'have' homesickness.

What exactly does le mal du pays mean word-for-word?

Le mal usually refers to an ache, pain, or sickness (like in avoir mal à la tête for having a headache), and du pays means 'of the country'. So it translates literally to 'the sickness of the country'.

Could I use a form of tout instead of chaque to mean 'every' here?

You could say tous les expatriés to mean 'all expatriates', but to emphasize 'each' or 'every' individual person, you use chaque. Remember that chaque is always followed by a singular noun, whereas tous les needs a plural noun.

Is there a liaison in the phrase de temps en temps?

Yes! The usually silent 's' at the end of the first temps connects to the vowel in en, creating a 'z' sound. It connects smoothly and is pronounced somewhat like 'deuh tahn zahn tahn'.