Pedals aren't going on?

A few tips to help get the pedals on the bike:

"We have a 48 Frog. We initially put the pedals on but our daughter was not ready pedal so removed the pedals to use as a balance bike. Now ready to try again with pedals but the left pedal won't screw back on. Not sure why. Right one is completely fine and very easy to screw on. Please could you advise what we need to do to resolve as our bike is not being used to full potential"

Check you're screwing in the right direction!

Watch out, the left pedal will screw on in the opposite direction to the right one.      

Check the thread is clean.

Use a soft, damp cloth to carefully remove any residue from the thread. Be careful not to scratch or make further dents to the thread, especially if there is grit in the thread. 

"Wiping the thread thankfully did the trick. Thanks for the tip. All ready to try pedalling!"