Save the emergency numbers before you need them, ideally on day one. Every country has its own set: 112 works across the European Union and in many other countries as a general emergency line, 911 covers North America and several other nations, and countries like India, Japan, Australia and others each have their own numbers for police, fire and ambulance, sometimes separate ones for each service. A quick check of your destination's official government or tourism site gives you the exact list, and many tourist destinations also run dedicated tourist police or tourist assistance hotlines with foreign language support.
English availability is genuinely hit and miss. Big-city dispatchers and tourist hotlines often manage English, but rural operators frequently do not, so knowing how to say your location and the word for help in the local language is smart insurance. Speaking slowly and stating your address first helps regardless.
Round out your emergency list with three more entries: your travel insurer's 24-hour assistance line, which can coordinate care in English almost anywhere; your embassy's emergency number; and your hotel's front desk, which can call local services and translate for you in a pinch.