Grow business in Europe if you only speak English
Europe has many different languages. It gives the continent its colour and helps to preserve the different cultures. It also makes it difficult to do business in new European markets. With a few exceptions (e..g. Latin America, Canada) most people from outside of Europe can only speak English to make their first connections on European markets. This of course is not an advantage in competition with local companies.
If you only speak English, which are the priority markets? Of course the UK is a target market as English is their language. Also, it is the first market that is approached by almost all people that speak English and want to expand to Europe, so sometimes there is more competition than in other European markets. Then there are the smaller but wealthy Dutch and Scandinavian markets, where over 90% of the population speaks English. Followed by Germany, Belgium and Switzerland with between 50-60% of the population speaking English. South of Belgium (France, Spain, Italy, Portugal) are much more difficult to establish business with only English as available language.
Of course you can hire external business development specialist or hire local staff that speak local languages well to do the job. But often this is only done after the possibilities in the English speaking regions have been assessed.