The £20 pound notes in question can not be used to purchase goods, however you can bank them, but you would be better of selling them as they will have more value if they are not forgeries as they were rife in them days.
If you hold the notes up to a light you will see watermarks in the paper which if I remember rightly will depict a picture of the queen, but they are quite worn so I would suggest looking on ebay for the same bank notes in finished auctions. This is the info I have found.
380 20 Pounds VG VF UNC
ND (1970-91). Purple on multicolor underprint. Queen Elizabeth II
in court robes at right. Back: Shakespeare statue at center right.
Watermark: Shakespeare.
a. Watermark: Queen Elizabeth II. Signature J. S. Fforde. (1970). 60.00 175. 500.
b. Watermark as a. Signature J. Page. (1970-80). FV 55.00 175.
c. Watermark as a. Signature D. H. F. Somerset. (1981-84). FV 65.00 210.
d. Watermark: Shakespeare. Modified background colors.
Segmented security thread. D. H. F. Somerset. (1984-88).
FV 55.00 165.
e. Signature G. M. Gill (1988-91). FV 55.00 160.
s1. Specimen. As a. — — 2000.
s2. Specimen. As d. — — 1800.
It's quite a bit of money there... but I usually keep my old notes just because I found it in circ or kept it from a while back. But it's up to you. They're beautiful notes!
University is time consuming, cherish your free time!
Portugal is really nice. Coin shops there...no. Overpriced everywhere.
You'll enjoy Portugal. Keep distance when driving. And attencao is pronounced attencion (cao = cion) the a has a ~ accent on it and the c has a little backward c on its bottom.
University is time consuming, cherish your free time!
That backwards c that you refer to...more like a 5 is called a cedilla. It is in French softening the c, much like ce in our language. Francois, Francais, pence, lice. Creating a s sound.