Sometimes, it’s even tricky for me to say English words that have /l/ and /r/ in the same word! Sometimes it’s tricky because the /l/ and /r/ are close together, or because the word is long with multiple /l/ and /r/ sounds in it. Basically, to pronounce these /l/ -/r/ words well, you need to just practise them till your mouth can make them smoothly in your everyday speech.
You may need to learn how to pronounce either of these sounds first (we have lots of material and training on this in our courses). Then once you are clear about the different production of the /l/ and /r/ sounds, it makes it much easier for your mouth to get from one to the other in words that have both sounds in them.
You are alternating between raising your tongue up at the front of your mouth for /l/, to raising it up more towards the middle of the mouth for /r/.
You could even use a famous English tongue twister to practise this:
‘Red leather, yellow leather’ – said over and over, and of course getting faster after a while!
English Words With l And r In The Same Word
ruler (American accent the /r/ in ‘er’ is also pronounced)
improperly (American- the /r/ in ‘er’ is also pronounced)
labouring / laboring
properly (American – the /r/ in ‘er’ is also pronounced)
propeller (American – the /r/ in ‘er’ is also pronounced)
centralise / centralize
Best wishes, Esther