The set of consonant pairs that may appear at the beginning of a word (excluding Lojbanized names) is far more restricted than the fairly large group of permissible consonant pairs described in Section 3.6. Even so, it is more than English allows, although hopefully not more than English-speakers (and others) can learn to pronounce.
There are just 48 such permissible initial consonant pairs, as follows:
bl | br | ||||||
cf | ck | cl | cm | cn | cp | cr | ct |
dj | dr | dz | |||||
fl | fr | ||||||
gl | gr | ||||||
jb | jd | jg | jm | jv | |||
kl | kr | ||||||
ml | mr | ||||||
pl | pr | ||||||
sf | sk | sl | sm | sn | sp | sr | st |
tc | tr | ts | |||||
vl | vr | ||||||
xl | xr | ||||||
zb | zd | zg | zm | zv |
Lest this list seem almost random, a pairing of voiced and unvoiced equivalent vowels will show significant patterns which may help in learning:
pl | pr | fl | fr | ||||||||
bl | br | vl | vr | ||||||||
cp | cf | ct | ck | cm | cn | cl | cr | ||||
jb | jv | jd | jg | jm | |||||||
sp | sf | st | sk | sm | sn | sl | sr | ||||
zb | zv | zd | zg | zm | |||||||
tc | tr | ts | kl | kr | |||||||
dj | dr | dz | gl | gr | |||||||
ml | mr | xl | xr |
Note that if both consonants of an initial pair are voiced, the unvoiced equivalent is also permissible, and the voiced pair can be pronounced simply by voicing the unvoiced pair. (The converse is not true: cn is a permissible initial pair, but jn is not.)
Consonant triples can occur medially in Lojban words. They are subject to the following rules:
Lojbanized names can begin or end with any permissible consonant pair, not just the 48 initial consonant pairs listed above, and can have consonant triples in any location, as long as the pairs making up those triples are permissible. In addition, names can contain consonant clusters with more than three consonants, again requiring that each pair within the cluster is valid.