Yes! To look up and save a phrase (called creating a LingQ, or LingQing the phrase), use your cursor to click, drag, and select the phrase you want to LingQ. We highly encourage you to LingQ popular phrases as they help you learn the language better.
You will then see the phrase turn blue and see available translations in the dashboard at right. Select the translation you want to assign to the phrase or make your own by clicking one of the integrated dictionaries.
Important: Don't LingQ every phrase. Only LingQ phrases that seem to be useful in the language, such as common turns of phrase or idioms. Saving and studying these phrases will help you become more natural-sounding as you use the language.
You can still save LingQs of the individual words within the phrases that you highlight as well.