This one might surprise you but sometimes you really should be using one or two emojis. If you think you’re being terse or something might come across with the wrong tone, a well-placed emoji can make all the difference. Just don’t overuse them. I tell my students to use a maximum of two per email.
13 writing habits that are making you look bad
Rob McTaggart
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This is probably true in a formal or conversational context. On the flip side there was an interesting correlation with our marketing research recently that actually showed people clicked into our ads more often when the sentence ended with an emojii !