Just about all Belgian coins have legends in two languages:
French: ROI DES BELGES, QUATRE BELGAS
Dutch: KONING DER BELGEN, VIER BELGA
No matter which coin you have, it is made of nickel, not silver, and this lowers value somewhat.
COINS WITH EITHER FRENCH OR DUTCH INSCRIPTIONS:
worn: $20 US dollars approximate catalog value
average circulated: $50
well preserved: $100
fully uncirculated: $200
There is a twist with one of these coins. Sometimes you find a 1932 20 francs with French inscriptions that has medal alignment instead of the normal coin alignment. These are worth more:
1932 20 FRANCS WITH MEDAL ALIGNMENT:
worn: $50 US dollars approximate catalog value
average circulated: $150
well preserved: $300
fully uncirculated: $600
To find out if your coin has medal alignment or not, do this. Hold the coin between your thumb and forefinger with your thumb on the bottom and forefinger on top. Turn the coin from left to right, like turning a page in a book. If the pattern on the other side is right-side up, you have medal alignment. Otherwise, if the pattern is up-side down, you have coin alignment. Coin alignment carries no premium value.